The other key component of Darwin’s argument in Chapter I is his use of the term selection to analyze the development of race types within species. In discussing selection, he notes that some traits are more useful or helpful than others and that these traits will be selected both consciously (by breeders) and unconsciously as the species evolves. Unconsciously selected traits develop naturally over time, often helping certain species adapt to their environments and increase their rates of survival. For example, a trait that would allow a species to survive famines or accidents might have been unconsciously selected if all other species died when a natural disaster occurred. Famines and accidents are natural occurrences, so the process of unconscious selection hints that natural selection accounts for species development in the wild. Darwin’s discussion of selection in Chapter I lays the groundwork for the crux of his evolutionary theory: his argument for natural selection.

Through his own observations and experiments, Darwin suggests that scientific methodology must be used to begin to understand the mysteries of nature—mysteries that heretofore had been unexplained or attributed to the workings of God. Moreover, Darwin illustrates the importance of inductive reasoning, or drawing conclusions from examples and observations, to the scientific process. By using examples taken from scientific observation, Darwin establishes principles of species development that would be impossible to infer on the basis of existing scientific thought alone. By drawing on specific observations, experiments, and conclusions based on research and evidence, Darwin is able to negate previously held ideas, such as the possibility of multiple parent species and Lamarck’s notion of the supposed dominant role of the environment in the development of variation. And finally, Darwin acknowledges that science still does not fully understand such concepts as the workings of heredity in reproduction. This kind of acknowledgment recognizes the limits of scientific inquiry and experimentation. Darwin’s scientific methodologies and processes point not only to the theories drawn from experimental and inductive reasoning but also to the uncertainties and disagreements inherent in the study of science.